Ok sorry didn't mean for it to be too open, I looking to develop skills as I am in becoming a computer programmer.
Its just I feel that Hillegass book is basic when you start to learn some things and im looking for a more advanced book.
Hope this help. Thanks
Stephen
Sorry if I came across as being critical, I was just trying to elicit more context.
This recent thread was about life in the industry.
https://forums.macrumors.com/threads/705761/
It might not really be what you're asking, but it has some advice/info.
I'm not sure what sort of study program you are in, but assuming your college/university has computer science classes and professors I think you should have access to advisors who can suggest a set of courses. (In the US, college and university are used pretty much interchangeably if you are trying to get a 4-year degree called Bachelor's. I get the impression that might not be true in Europe.)
Anyway, if you've done the equivalent of an Intro to Programming class by using the Hillegass book, I think the next step in CS would be to study data structures and algorithms. In my opinion, the book I used in college (Algorithms in C by Robert Sedgewick) is not particularly easy to use by oneself. In my experience, however, this area of study is often used in technical interviews when trying to get a programmer job.
I don't have any experience with either of the two books mentioned in this thread, but I think either would be good for continuing Macintosh programming. So if you have a project idea you want to do for yourself, I think the XCode Unleashed would be helpful for organizing your code and understanding the lifecycle concepts for a larger program. The other book is probably good for more advanced functionality, but I suspect you won't have any good guidelines on when to use those system capabilities like pipes, sockets, signals, threads, etc.